The primary objective of this research is to explore patterns of peer interaction in the classrooms of a desegregated middle school. Attention is being focused both on the quantity of such behavior and its quality. Data has been gathered in both eighth and sixth grade classrooms which were observed twice a week for a full semester. In each class a randomly selected sub-sample of students was observed. If the student whose behavior was being coded was in the midst of an interaction, the race, sex and role (student, teacher, etc.) of the interactant were recorded. Also coded were the form (verbal, physical, etc.), content (task, social, etc.) and tone (positive, neutral, negative), of the behavior. Analyses to date show a strong tendency for children in both grades to interact more with children of their own sex than with children of the other sex. A similar though weaker tendency was found in both grades for children to interact more with those of the same race than the other race. In the eigth grade this finding was primarily to the girls' strong propensity for in-group behavior. Although sixth grade boys and girls both showed this tendency, girls were significantly more likely to do so. Preliminary analyses of the quality of the behavior are now underway. In general, they suggest relatively little difference in the quality of interracial and intraracial interactions. Also, they suggest that very little negative behavior occurs in either intraracial or interracial interactions. Further exploration of the data on the quality of peer behavior is now in progress.